Brassica Queries.

[Stringfellow]

Hi. Two queries relating to brassicas;

I have a tray full of plants ready to go out and was planning on interplanting my onions with some of these; I figure these will all need meshing against butterflies?

On that note, the same plants appear to have already been visited by the aforementioned butteflies as there are tiny catterpillars nibbling away at there lovely leaves. These plants have lived in the greenhouse on staging; how do gardeners maintain ventilation in their glass houses yet still keep these butterflies off new brassica plants; is meshing over doors and windows the answer? Charles, I have not seen any photos of you using this method – what do you do in this situation?

Thank you and first harvest just coming in here oop north 🙂

[charles]

Its not cut and dried, I had some caterpillars on module plants only once in the last three years (Sep 13) after a hot summer when there were many around. But I raise plants in a greenhouse with the door mostly shut, perhaps its side and roof windows offer less point of entry.
Perhaps it would be worth a mesh where doors are open, but not windows I think.
Also if the weather stays wet, young brassicas grow away better without mesh and I have mine uncovered at the moment, until mid July probably.

[Karen]

Hey Stringfellow,

My kale seedlings were just pricked out and sitting in their module cells and I keep them covered as I have been seeing some butterflies recently.

My other brassicas (red and white cabbage and Brussel sprouts) are protected in mesh as I lost my Spring batch of brassicas to root larvas. Not taking any chances as it is my very first attempt to grow cabbages and Brussel sprouts.

Keeping my fingers crossed!

[bluebell]

I have net curtains secured oh a wire top and bottom across my doors – primarily to keep the cats out and my. Neighbours laugh at me but a quick cheap solution.

[Stringfellow]

Thanks all, it’s really helpful to know what others are doing at these times. I’m now wondering what did lay eggs on these module plants! I’ve squished them anyway. There’s always something trying to eat ya veg – considering signing up with ‘anti-pesto’, gettting Wallace and Gromit on the case!

[ElizaD]

I have strange little white lines appearing on my cabbages . They are growing well otherwise. It’s not leaf miner I think because the lines are quite short and very straight. Pulled one cabbage out when I first noticed it and put in a replacement but now two or three others seem to have the same problem. Didn’t have any problems at all growing these cabbages last year (greyhound, from seed). The plants are covered in mesh and have collars around their necks, again as last year. Any ideas?

[Julie Harris]

Hi Stringfellow
Here in NW Scotland we had a plague of diamondback moths a few weeks ago and I found a tray of 24 assorted brassicas had been attacked and ruined by their caterpillars – in the greenhouse. I do have the door open as I only have roof windows otherwise, but have never had this problem before. The pests were still minute but visible to the naked eye and if you shook the plants (what was left of them) gently the caterpillars would dangle off them on a thread like a spider.

[charles]

So diamondback moths sound bad, thanks for the tip Julie.
I am unsure what the white lines are caused by but would not pull out the plants, as long as the soil is in good heart. Its fine cabbage weather now and I back them to recover.
My Greyhound had many ugly, pale patches on outer leaves in May but by June they looked clean, with splendid hearts.

[Stringfellow]

Thanks Julie, it’s certainly a possibility and they were very tiny caterpillars. I guess a simple net curtain over plants is a quick and easy preventative measure for those that leave the greenhouse door open.

The plants are mostly out in their final positions now and, I hope, they will get their feet down and grow away from these tiny nibbles.

[al28lily]

Hi Charles

This is brassica related but unrelated to other queries. I attended your talk last week in Hitchin and bought one of perennial kale plants from you. I just wanted to double check on it’s name (Daubenton??) so I can give it the best start.

I was thinking of planting it out now on our allotment in a bed containing other perennials, globe and Jerusalem artichoke. We have lots of pigeons and parakeets which devour our brassicas so will use the trusty micromesh to protect it while small.

Your talk was excellent! I have been trying to persuade my husband of the merits of no dig and after attending last week he is a convert. We just need to source/produce more compost!

I am new to forums but may post something about compost as I am an enthusiast.

[charles]

Glad you liked my talk, and the kale is Taunton Deane. Its taller than Daubentons, up to five or six feet eventually so needs good pigeon-protection.
Best of luck sourcing compost.

[Karen]

Hey Charles,

I thought caterpillars mostly went after brassicas, however, just discovered a few days ago that somehow some of them managed to get into my lettuce seedlings together with endives and kale in their module trays under mesh.

Oddly, it was mostly the lettuce and endives that received the damage from these pesky minute caterpillars! I am guessing that the mesh holes are not tiny enough. And oddly enough my other older brassicas (cabbages and Brussel sprouts – coming along VERY NICELY I gotta say, fingers crossed!) under the same mesh sizes have not had this kind of damage.

Thankfully I have more than enough seedlings. I have been picking these caterpillars off with tweezer as they are quite tiny.

[Karen]

Hey Charles,

I have just removed the mesh on my brassica bed and everything looks really good aside from the odd hole in some of the leaves. Found 1 big fat bright green caterpillar, wonder how it managed to hijack onto the leaves…. hmmmm. …

I am thinking of not putting the mesh back on and give a little more ventilation to the plants as they are getting really big and taller now.

Would you leave the mesh on or off if it was you? There are still some white butterflies hovering about and would you reckon they would do much damage now that these plants are relatively big? I will still be on the lookout for caterpillars and other bugs.

I am very excited and anxious as well as I am looking forward to this harvest. My first attempt with cabbages and Brussel sprouts.

[charles]

How much damage depends on the weather mostly, and hot sunny conditions favour butterflies.
Yes its difficult to keep large plants covered and Brussels often survive summer then make their harvest when caterpillars are not there.
Its up to you. Squash any you see, or spray Dipel.

[Karen]

Ok will do thanks. Will be extra vigilant and be on the lookout. Fingers crossed!

[Author]

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